A blacklist and IP-address database, formerly privately owned but now part of the email vendor Ironport. Many ISPs check the IP addresses of incoming email against Spamcop’s records to determine whether the address has been blacklisted due to spam complaints.
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Building Your Business with an Opt-in List
Before revealing the secrets of the trades, here are myths and fallacies that need to be cleared before one indulges into building an opt-in list.